where/how can I change my info from 1040SR to 1040

The 1040SR is EXACTLY the same as the 1040.  The line numbers are the same.   They both use the same instructions and tax calculations.  You automatically get the 1040SR if one spouse 65 or older.

If you use the Desktop program you can switch to forms and the Info Wks part II has a selection to select 1040SR or not.  You can not change it in the Online versions.   In the Online version if you want to use the regular 1040 form, you can print out the 1040SR and copy the amounts onto a blank 1040 and then mail your return.

Since you are doing a 2023 tax return you must be using the Desktop program.   Here’s a screenshot of where to pick which one to print.